x86, sparseirq: clean up Kconfig entry
Impact: improve help text
Signed-off-by: Ingo Molnar <mingo@elte.hu>
diff --git a/arch/x86/Kconfig b/arch/x86/Kconfig
index d14a880..e4c038a 100644
--- a/arch/x86/Kconfig
+++ b/arch/x86/Kconfig
@@ -242,10 +242,14 @@
bool "Support sparse irq numbering"
depends on PCI_MSI || HT_IRQ
help
- This enables support for sparse irq, esp for msi/msi-x. You may need
- if you have lots of cards supports msi-x installed.
+ This enables support for sparse irqs. This is useful for distro
+ kernels that want to define a high CONFIG_NR_CPUS value but still
+ want to have low kernel memory footprint on smaller machines.
- If you don't know what to do here, say Y.
+ ( Sparse IRQs can also be beneficial on NUMA boxes, as they spread
+ out the irq_desc[] array in a more NUMA-friendly way. )
+
+ If you don't know what to do here, say N.
config NUMA_MIGRATE_IRQ_DESC
bool "Move irq desc when changing irq smp_affinity"